24 



species lias always a white base, being immaculate beneath the 

 inferior band. 



H. INORNATA. — Shell subglobose, pale yellowish horn color, 

 polished ; whorls five, rounded, -wrinkled ; spire convex ; suture 

 not deeply impressed ; umbilicus small, profound ; aperture wide, 

 at the junction of the labia with the penultimate whorl shorter 

 than the width of the mouth ; labrum simple. 



Inhabits Pennsylvania. Grreatest width less than seven-tenths 

 of an inch. 



This species has a strong resemblance to H. ligera, but in addi- 

 tion to its superior magnitude, its aperture is proportionally wider, 

 a character which of course gives the whorls a greater breadth ; 

 the whorls are also fewer in number, and the distance between the 

 terminations of the lips is very perceptibly less than the width of 

 the aperture, the reverse of which obtains in the ligera. 



IT. INDENTATA. — Shell depressed, pellucid, highly polished ; 

 whorls four, with regular, distant, subequidistant, impressed lines 

 across, of which there are about twenty-eight to the body whorl, 

 all extending to the base ; suture not deeply indented ; aperture 

 rather large ; labrum simple, terminating at its inferior extremity 

 at the centre of the base of the shell ; umbilicus none, but the 

 umbilical region is deeply indented. 



Greatest breadth one-fifth of an inch. Animal blued-black, 

 immaculate. 



My cabinet and that of Mr. Wm. Hyde. Several specimens 

 occurred at Harrigate, the country residence of my friend Mr. 

 Jacob Gilliams, adhering to stones and logs in moist places. Mr. 

 Hyde obtained many individuals in New Jersey. It may readily 

 be mistaken for H. arborea, but it. is destitute of the umbilicus, 

 instead of which there is an indented centre to the base, in which 

 the labrum terminates. The spire is very much depressed, and 

 the surface prettily radiated by distant impressed lines, the inter- 

 stices being perfectly smooth. 



H. LINEATA. — (Vol. i., p. 18.) On examination of several in- 

 dividuals of this species, I have ascertained that a character exists 

 in this species that was altogether wanting in the specimen from 

 which I drew out the description published in the first volume of 

 this work. As the shell is somewhat translucent, two pairs of 

 white teeth, remote from each other, may be observed through the 



